(a) Field
Exemplary embodiments of the invention relate to a display device and a driving method thereof, and particularly relate to an organic light emitting device and a driving method thereof.
(b) Description of the Related Art
In general, an organic light emitting display device, which is a display device that electrically excites a fluorescent organic material to emit light to display images, includes a hole injection electrode (anode) and an electron injection electrode (cathode), and an organic emission layer disposed therebetween. The organic light emitting display device is a self-emission type of display device that emits light while recombining holes and electrons, and resulting excitons become extinct if charges are injected to the organic emission layer. To improve luminous efficiency of the organic emission layer, an electron transport layer (“ETL”) and a hole transport layer (“HTL”) are included, and an electron injecting layer (“EIL”) and a hole injecting layer (“HIL”) may be further included.
A current amount of a driving thin film transistor that supplies a current for the light emitting to the organic emission cell is controlled by a data voltage applied through a switching element, and the current flows to the organic emission cell through the driving thin film transistor, thereby emitting the light.
However, when the driving thin film transistor is driven for a substantially long time, a characteristic (e.g., a threshold voltage) of the driving thin film transistor is changed. As a result, when the same data voltage is applied, the current flowing to the organic emission cell is changed as the characteristic of the driving thin film transistor is changed such that the display luminance is changed.